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/** @file pa_fuzz.c
@ingroup examples_src
@brief Distort input like a fuzz box.
@author Phil Burk http://www.softsynth.com
*/
/*
* $Id$
*
* This program uses the PortAudio Portable Audio Library.
* For more information see: http://www.portaudio.com
* Copyright (c) 1999-2000 Ross Bencina and Phil Burk
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files
* (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge,
* publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
/*
* The text above constitutes the entire PortAudio license; however,
* the PortAudio community also makes the following non-binding requests:
*
* Any person wishing to distribute modifications to the Software is
* requested to send the modifications to the original developer so that
* they can be incorporated into the canonical version. It is also
* requested that these non-binding requests be included along with the
* license above.
*/
#include <stdio.h>
#include <math.h>
#include "portaudio.h"
/*
** Note that many of the older ISA sound cards on PCs do NOT support
** full duplex audio (simultaneous record and playback).
** And some only support full duplex at lower sample rates.
*/
#define SAMPLE_RATE (44100)
#define PA_SAMPLE_TYPE paFloat32
#define FRAMES_PER_BUFFER (64)
typedef float SAMPLE;
float CubicAmplifier( float input );
static int fuzzCallback( const void *inputBuffer, void *outputBuffer,
unsigned long framesPerBuffer,
const PaStreamCallbackTimeInfo* timeInfo,
PaStreamCallbackFlags statusFlags,
void *userData );
/* Non-linear amplifier with soft distortion curve. */
float CubicAmplifier( float input )
{
float output, temp;
if( input < 0.0 )
{
temp = input + 1.0f;
output = (temp * temp * temp) - 1.0f;
}
else
{
temp = input - 1.0f;
output = (temp * temp * temp) + 1.0f;
}
return output;
}
#define FUZZ(x) CubicAmplifier(CubicAmplifier(CubicAmplifier(CubicAmplifier(x))))
static int gNumNoInputs = 0;
/* This routine will be called by the PortAudio engine when audio is needed.
** It may be called at interrupt level on some machines so don't do anything
** that could mess up the system like calling malloc() or free().
*/
static int fuzzCallback( const void *inputBuffer, void *outputBuffer,
unsigned long framesPerBuffer,
const PaStreamCallbackTimeInfo* timeInfo,
PaStreamCallbackFlags statusFlags,
void *userData )
{
SAMPLE *out = (SAMPLE*)outputBuffer;
const SAMPLE *in = (const SAMPLE*)inputBuffer;
unsigned int i;
(void) timeInfo; /* Prevent unused variable warnings. */
(void) statusFlags;
(void) userData;
if( inputBuffer == NULL )
{
for( i=0; i<framesPerBuffer; i++ )
{
*out++ = 0; /* left - silent */
*out++ = 0; /* right - silent */
}
gNumNoInputs += 1;
}
else
{
for( i=0; i<framesPerBuffer; i++ )
{
*out++ = FUZZ(*in++); /* left - distorted */
*out++ = *in++; /* right - clean */
}
}
return paContinue;
}
/*******************************************************************/
int main(void);
int main(void)
{
PaStreamParameters inputParameters, outputParameters;
PaStream *stream;
PaError err;
err = Pa_Initialize();
if( err != paNoError ) goto error;
inputParameters.device = Pa_GetDefaultInputDevice(); /* default input device */
if (inputParameters.device == paNoDevice) {
fprintf(stderr,"Error: No default input device.\n");
goto error;
}
inputParameters.channelCount = 2; /* stereo input */
inputParameters.sampleFormat = PA_SAMPLE_TYPE;
inputParameters.suggestedLatency = Pa_GetDeviceInfo( inputParameters.device )->defaultLowInputLatency;
inputParameters.hostApiSpecificStreamInfo = NULL;
outputParameters.device = Pa_GetDefaultOutputDevice(); /* default output device */
if (outputParameters.device == paNoDevice) {
fprintf(stderr,"Error: No default output device.\n");
goto error;
}
outputParameters.channelCount = 2; /* stereo output */
outputParameters.sampleFormat = PA_SAMPLE_TYPE;
outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
outputParameters.hostApiSpecificStreamInfo = NULL;
err = Pa_OpenStream(
&stream,
&inputParameters,
&outputParameters,
SAMPLE_RATE,
FRAMES_PER_BUFFER,
0, /* paClipOff, */ /* we won't output out of range samples so don't bother clipping them */
fuzzCallback,
NULL );
if( err != paNoError ) goto error;
err = Pa_StartStream( stream );
if( err != paNoError ) goto error;
printf("Hit ENTER to stop program.\n");
getchar();
err = Pa_CloseStream( stream );
if( err != paNoError ) goto error;
printf("Finished. gNumNoInputs = %d\n", gNumNoInputs );
Pa_Terminate();
return 0;
error:
Pa_Terminate();
fprintf( stderr, "An error occurred while using the portaudio stream\n" );
fprintf( stderr, "Error number: %d\n", err );
fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
return -1;
}
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